Significant disorder-induced enhancement of the magnetization of Fe2CrGa by ball milling

It is reported that ball milling gives rise to a different atomic configuration in Fe2CrGa than the order obtained upon preparation by arc melting. After ball milling, the magnetic moment has values of 3.2 to 3.9 μB/f.u., which is significantly higher than in arc-melted samples, and the Curie temperature increases by about 200 K. Combination of first-principles calculations and experimental results indicates that Fe2CrGa crystallizes in the Hg2CuTi-based structures with either Fe-Ga or Cr-Ga disorder, depending on the preparation method. It is shown that magnetic interactions play a crucial role in adopting atomic configurations which disobey the empirical rule.